Conventional operating table lamps (e.g., as described in German Patent No. 198 38 627 A1) include at least one radiation source and at least two reflectors. To produce an illumination field from the lamp with few shadows, the radiation emitted by the operating lamp impinges onto the illumination field at least two different angles of incidence. The angles of incidence of the radiation can thereby be adjusted by changing the separation between at least two reflectors or between a reflector and the radiation source.
Prior art operating lamps cannot change of shape of the illuminated field (e.g., the illuminated area on the operating table) as may be required for individual applications.
Conventional operating lamps have a fixed light distribution. Operating lamps must meet the requirements given in various different illumination situations. For example, large-surface wounds require a large amount of light from the edge of the lamp to prevent shadows and provide light behind obstacles. For wounds with a smaller diameter and large depth, light from the center of the lamp is required. These extreme requirements are only poorly met by conventional operating lamps, because conventional lamps generally exhibit compromises with respect to light distribution.
For this reason, head lights are conventionally used today, as are optical fibers that can be introduced into the wound. However, a disadvantage of such light sources is that the head light or the optical fiber limits the operating surgeon (e.g., due to the un-ergonomic posture required of the operating surgeon to hold the head lamp) or limits the light power due to soiling and problems with hygiene when the light source is introduced into direct contact with the wound.